Note: If you'd like to use boneless, skinless chicken thighs, I would cook for a bit less and check the internal temp for doneness.
Place the chicken in a resealable bag or a baking dish. Whisk together the oil, vinegar, garlic, basil and a big pinch of salt and pepper. Pour it over the chicken and make sure it’s covered evenly. Stick in the fridge and marinate for at least 30 minutes or even overnight.
When ready to cook, remove the chicken from the fridge about 20 minutes before to take the chill off. Preheat the oven to 400 degrees F.
Heat a large oven-safe (cast iron, ceramic, etc) skillet over medium heat, with a drizzle of olive oil. Grab a piece of chicken with tongs and let the excess marinade run off. Place in the skillet and repeat with remaining chicken. Sear until golden and deeply browned on both sides.
Turn off the heat until the chicken. Top with a few spoonfuls of pesto, right on top of the chicken. Top with a slice or two of fresh mozzarella.
Place the whole skillet in the oven and bake for 10 to 15 minutes, or until the internal temperature reaches 165 degrees F. Remove and cover with fresh basil and parmesan. Serve!
Note: I like to stir pesto into a grain, like rice or couscous, etc, for a super easy side dish.